Fair Value Measurements (Details) (USD $)	3 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012	Dec. 31, 2011
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of long-term debt	$ 268,000,000		$ 280,500,000
Carrying amount of long term debt	275,000,000
Foreign currency forward contracts, gross notional value	1,840,000,000		1,950,000,000
Foreign currency forward contracts, net notional value	798,600,000		886,600,000
Foreign Exchange Contracts, Fair Value Gain (loss)	7,200,000	400,000
Deferred compensation plan, contra-equity, shares held in trust	8,100,000		7,600,000
Fair value of investments	75,096,000	77,711,000	63,579,000	23,169,000
Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deferred compensation plan liabilities	74,833,000		62,095,000
Foreign currency forward contract, current asset amount	15,538,000		4,351,000
Deferred compensation plan assets	76,464,000		60,523,000
Foreign currency forward contract, current liability amount	8,319,000		10,074,000
Foreign Exchange Contract [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset, Fair Value, Gross Asset	15,700,000
Derivative Asset, Fair Value, Gross Liability	200,000
Derivative Liability, Fair Value, Gross Liability	9,600,000
Derivative Liability, Fair Value, Gross Asset	$ 1,300,000